Researcher: Pollution Limits Sun in China

BANGKOK, Thailand - China's skies have darkened over the past 50 years, possibly due to haze resulting from a nine-fold increase in fossil fuel emissions, according to researchers from the U.S. Department of Energy.
The researchers, writing in this month's edition of Geophysical Research Letters, found that the amount of solar radiation measured at more than 500 stations in China fell from 1954 to 2001 despite a decrease in cloud cover.
"Normally, more frequent cloud-free days should be sunnier and brighter but this doesn't happen in our study," said Yun Qian of the energy department's Pacific Northwest National Laboratory in Washington state.

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